In general, carbon monoxide (CO) is hazardous to a person's health. When breathed, carbon monoxide replaces oxygen in the bloodstream. Mild carbon monoxide poisoning results in flu-like symptoms, while more serious poisoning leads to difficulty in breathing and even death via suffocation.
Carbon monoxide poisoning is believed to be the leading cause of accidental poisoning deaths in the United States. On the average, approximately 5,000 deaths occur, and over 20,000 illnesses result each year from carbon monoxide poisoning.
Carbon monoxide is an invisible, odorless, colorless gas that is a by-product of the incomplete combustion of fossil fuels. This makes it difficult for an individual to recognize the presence of excessive carbon monoxide. In the home, heating and cooking equipment are common potential sources of carbon monoxide. Furnaces are another source of carbon monoxide. Furnaces may be installed at various areas within a home such as, the basement, the attic or within a closet. Any of theses installations could infiltrate the house with carbon monoxide in the event of a malfunction. A mechanical failure such as a fractured heat exchanger may force carbon monoxide through the duct-work of the house to create a toxic condition. Motor vehicles also produce carbon monoxide that can reach dangerous levels when left running in a closed or poorly ventilated garage. This carbon monoxide can infiltrate into a home from an attached garage that may reach toxic levels.
As a result, carbon monoxide detectors are well known in the art. Current carbon monoxide detectors typically monitor carbon monoxide levels in one of three processes. The first process is based on electrochemical technology that uses three platinum electrodes in an electrolyte solution that generate energy when they react with the carbon monoxide, thereby setting off an alarm. The second process uses metal oxide semiconductor technology that is heated every few minutes to react with carbon monoxide and determine levels of that gas. The third process uses bio-mimetic technology that is designed to mimic the hemoglobin response to carbon monoxide, which is to change to a darker color as the level of carbon monoxide increases.
These conventional detectors are generally provided with an internal audible alarm that sounds when the presence of carbon monoxide is detected, similar to common household fire and smoke detectors, with the intention of alerting occupants of a building to enable evacuation and/or take other corrective measures as appropriate.
However, such audible alarms are ineffective when the homeowners are away from the home, at work, running errands, vacation etc. The homeowner may unknowingly return to the home contaminated with CO. The audible alarms are generally muffled so that they cannot be heard from an automobile approaching the home or entering the garage.
There have been attempts in the art to improve the performance of carbon monoxide detectors by causing them to open garage doors, operate fans or turn off devices that are producing carbon monoxide. For example, Hayashi, U.S. Pat. No. 3,826,180, discloses a ventilation fan system with smoke detector speed control. The device includes an electronic circuit that is actuated when a detecting element detects the existence of any smoke or gas in an enclosed area while a fan is in a manually selected slow rotating mode of operation or in a stand-by stopped position. Upon detection of smoke or a gas such as carbon monoxide; the fan is automatically put into full rotation mode in order to expel the smoke or gas. The device expels the smoke or gas through a window that includes solenoid operated shutters that are also controlled by the device.
Kelly, U.S. Pat. No. 4,197,675, discloses a sensing system for use in a garage or other similar enclosure having an automatic door operator for automatically opening a garage door responsive to a lack of sufficient oxygen therein. The device includes a gas detector located within the enclosure responsive to actuate a detection relay which in turn will close a normally open detection switch. The closing of the detection switch causes operation of the door opener to allow oxygen to enter into the enclosure through the door opening.
Duhame, U.S. Pat. No. 4,360,801, discloses a home security and garage door operator system. The system includes a gas sensor for detecting the level of toxic gas in the garage. When the gas level exceeds a predetermined threshold the garage door is automatically opened.
Vole, U.S. Pat. No. 4,819,551 discloses a safety system for smoke and fumes. The system includes a detector unit for detecting fumes, including carbon monoxide. The device is located in a garage, and circuitry controlled thereby automatically opens the garage door, or operates an exhaust blower, or both upon detection of carbon monoxide.
Murphy, U.S. Pat. No. 5,576,739, discloses a carbon monoxide safety system. The system measures noxious gas concentration in an affected space and controls the device producing the noxious gas for decreasing the concentration of the gas in the affected space. The invention is particularly described in relation to measuring carbon monoxide concentration in an automobile garage and for controlling the garage door opener circuit to open the garage door in response to a preselected concentration of carbon monoxide. Also described in particular is a system for deactivating a furnace operating circuit to turn off the furnace in the event of excessive carbon monoxide concentration.
Czeck et al., U.S. Pat. No. 5,947,814, discloses a garage carbon monoxide venting system. The gas venting system includes an electrically operated exhaust fan used in an enclosed garage to expel unwanted gases, especially carbon monoxide, to outside the garage and away from an attached residence.
Meneely, Jr., U.S. Patent Publication Nos. 2002/0111132 and 2003/0087600 disclose a carbon monoxide ventilation system, comprising a carbon monoxide sensor, a fan, and a vent. The carbon monoxide sensor supplies power to the fan when a threshold level of carbon monoxide is detected. The fan includes a motor and a propeller which draws air into the fan unit, and expels the air through the vent.
Dazurko et al., U.S. Patent Publication No. 2005/0212681, discloses a garage monitoring system for use with an automatic garage door opening mechanism that includes a carbon monoxide detector configured to sense the presence of carbon monoxide within the garage and generate an audible alarm when carbon monoxide reaches a predetermined level in the garage.
Winters et al., U.S. Patent Publication No. 2003/0020619, discloses a proactive carbon monoxide protection system that includes a carbon monoxide detector connected to a control module adapted to turn off the source of carbon monoxide, sound a central alarm, and alert an off-site monitoring station upon detection of carbon monoxide by the detector.
While these devices may be effective in some instances for reducing CO in a garage or home, they may also create additional problems for the home owner. For example, opening the garage door while the owner of the home is away breaches the security of the home by allowing easy entry to at least the garage and possibly the home itself. Automatic garage door operation may additionally trigger an alarm system. Absent a special signal to the alarm company, indicating high CO level, the police may be forced to unknowingly enter the home filled with dangerously high levels of CO in search of a burglar. Still yet, turning off an appliance such as a furnace without supervision can have devastating consequences to the home owner should he/she be away from the home. The pipes as well as other portions of the home could be frozen and permanently damaged causing extensive damage to the home.
Often high CO levels are associated with an automobile. Vehicles are often left running in the garage of a home for various reasons. Warming up the vehicle, talking on a cell phone, and going back into the home to retrieve a forgotten item are just a few of the reasons why an automobile may be left running in the garage. In the case of a town-home or apartment, a failed appliance or running vehicle may cause high CO levels in the adjacent dwellings.
Thus, there is a need for a new and improved monitoring and protection system that addresses the drawbacks and disadvantages of such prior CO monitoring devices. The system should monitor CO levels within the home and/or garage and upon the attempted opening of the garage door for entry to the home an internal monitor having a first transceiver should send a signal to a remote transceiver in the vehicle to indicate whether or not the building is safe to enter. The device may include one mode for when people are in the home and a second mode for when people are away from the home. The first mode should provide an audible alarm in addition to automatic opening of the garage door to vent gasses if the gas levels are high in the garage. In the second mode, a base monitor should send a signal to the remote transceiver to notify the person of a problem prior to entry into the dwelling. In addition the remote transceiver should continuously monitor the air conditions within the vehicle itself to alert the driver and/or passengers in the event the air becomes unsafe.